ENID, Okla. — Wide swings in spring temperatures, including a late March cold front that plunged much of the Southern Plains below the freezing mark, have raised fears of potential freeze damage for crops already stressed by a lack of moisture.

Freeze injury takes several weeks to appear and can be difficult to diagnose, but wheat farmers in Texas and southwestern Oklahoma are likely to see signs of it in coming days. Yellowed tillers, or plant shoots, are a common indicator.

Unusually low temps were “sufficiently cold to cause severe injury to wheat in advanced stages of growth,” cautioned Travis Miller, an agronomist with Texas A&M. “It’s a large and complex problem out there. But if you had wheat that was blooming and your temperatures got down to 26, you’re going to have some injury.”

Further north, experts gathering for an area-wide Canola College that drew nearly 300 farmers from at least four states, said freeze damage would remain a concern over the next couple of weeks although so far any damage locally was minimal.

“At the end of the day, I don’t know if what we’ve seen so far will have any effect,” said Tim Bartram, executive director of the Oklahoma Wheat Growers Association. “The heat and the moisture situation is a bigger concern.”

He predicts the state will harvest an average wheat crop at best, based on weather patterns resembling the 1950s and the likelihood that sustained drought relief won’t come until late summer at the earliest.

Agronomist Mark Hodges, who is director of Plains Grains Inc. and Oklahoma Genetics Inc., said much of the wheat was maturing slowly, and conditions had not been as unseasonably warm or as variable as they were a year ago. But he also said overall the wheat is hindered by a lack of tillers and poor root development.

“We can’t afford to lose any tillers (to freeze or other causes,)” he said. “Typically, we have primary tillers and a lot of secondary tillering. This year we don’t have as much of that luxury.”

Jeff Scott, who grows both wheat and canola near Pond Creek, Okla., said late freezes are always a threat. But he was more worried about whether the area would continue to receive needed precipitation.

Canola is less vulnerable to spring freeze than wheat, he said.

“As hardy as we’ve always thought wheat was, canola is proving itself to be even hardier,” noted Scott, who serves as president of the Great Plains Canola Association. “If we do get a freeze, the canola will just branch out lower down on the plant.”

Page 2 of 2 - Canola becomes most vulnerable to freeze after it bolts. That’s the stage where it begins to shoot vertically upward before blooming and setting seedpods, according to private crop consultant Chad Godsey of Stillwater.

Oklahoma State University canola specialist Josh Bushong, who goes by the Twitter handle “Tall Okie,” added that the maturity of wheat and canola was running close to average (compared to last year when it was nearly three weeks ahead of normal.) But he did say dry soils amplify the impact of unseasonable cold. Any severe dips in temperature would delay maturity and decrease yield potential, he predicted.

A key prospective plantings report, released in late March by the U.S. Department of Agriculture, triggered lower grain prices on the news that farmers intend to plant a record corn crop again this year. The report showed winter wheat acreage 2 percent higher than the previous year. Bartram, with the Wheat Growers association, was not surprised to see bearish numbers but pointed to the uncertainty still surrounding the future harvest.

“Kansas wheat acreage was predicted to be up considerably because they did not have a good summer crop season. They went back to wheat because it fits the current weather patterns better,” Bartram said. “What the plantings report indicates isn’t of huge importance. The big factor is going to be how much abandonment we have.”

As for the canola, Michael Stamm, Kansas State University canola breeder who collaborates on research projects with Colorado State, Texas A&M, Nebraska and New Mexico State, predicted an average crop or better was still possible across the region. Winter canola acreage has set new records each of the last three years, with roughly 280,000 acres now planted in Oklahoma, 30,000 in Kansas, and 10,000 in the Arkansas Valley of Colorado, he estimated. It is being grown successfully as far northwest as Torrington, Wyo.